Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Consolidated Statements of Comprehensive Income (Loss) [Abstract]
Net income	$ 139,590	$ 57,516	$ 50,782
Other comprehensive income (loss):
Changes in fair value of cash flow hedges and amortization of settlement swaps	3,402	7,707	(50,437)
Changes in fair value of marketable securities	1,411	1,330	5,357
Reversal of unrealized gains upon the sale of marketable securities	(1,082)	(4,286)	(12,027)
Total other comprehensive income (loss)	3,731	4,751	(57,107)
Comprehensive income (loss)	143,321	62,267	(6,325)
Comprehensive income attributable to noncontrolling interest	(14,527)	(10,751)	(10,752)
Comprehensive income (loss) attributable to the Company	$ 128,794	$ 51,516	$ (17,077)

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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